the idea is that the superblock ends up getting corrupted, whereas a standard RAID5/6 on ext4 wouldn’t, lol

Just do a search on your favorite search engine for “btrfs raid5/6 write hole bug” and you’ll see. If power gets cut, any file on the set of disks could be missing, or just have bunch of garbage.

I literally daily drive btrfs. Just don’t use a crappy drive or use raid5/raid6.